LED pin numbering is inconsistend between symbols, footprints and standad convention

[lenaschimmel]

This is a general warning that something is off here. I'm not yet sure about all the details.

At first I noticed that some LEDs in my LED Board A2 v1.0 (may not be committed and pushed at the time of this writing) did not light up, because I soldered them the wrong way. When I checked the PCB and Schematic in KiCad, I found that everything is chaos and it's a mystery how in the end only one chain of LEDs ended up in the wrong direction in the physical board.

• Symbols
  • LED:LED_Thermal_Pad (from Library)
    • 1=K, 2=A, 3=Thermal
  • LED_CREE_JSE28L3E5_Group_2 (self-drawn based on some existing symbol)
    • 1=A, 2=K
  • LED_CREE_JSE28L3E5_Group_2 (self-drawn based on some existing symbol)
    • 1=K, 2=A
• Footprints
  • LED_SMD:Luminous Devices A130 Package (self-drawn)
    • 1=K, 2=A, 3=Thermal
    • but silkscreen with a dot and a small "A" at the "K"-side
  • LED_SMD:LED_2835_CREE_JSE28L3E5_Big_Anode (self-drawn)
    • 1=A (big), 2=K (small)
    • silkscreen open at the "A"-side
  • LED_SMD:LED_2835_CREE_JSE28L3E5_1 (self-drawn)
    • 1=A (big), 2=K (small)
    • silkscreen open at the "K"-side

According to this comment: "K=1, A=2 is common standard that we should follow."

So the three-pin LED is the only one that has the correct order in the Symbol and in the Footprint, yet the only one that I soldered incorrectly due to the error in the silkscreen.

To make things more even complicated: I knew early on that CREE LEDs would have conflicting pin assignments with the J-series, depending on color. For some, the bigger pad is the Cathode (K), for some, the bigger one is the Anode (A). When I first ordered a PCM with assembly for the LEDs (Board A version 1.0), I made sure to make it clear to the manufacturer how the LEDs should fit. But in the exported BOM, the rotation angles seemed off.

For unrelated reasons, I had to redo large parts of the PCB layout to make it possible to manufacture. or the re-upload, I cleaned up the symbols and/or footprints of the LEDs to make it less confusing (and of course told the manufacturer about the change). Because the first upload was never manufactured, I kept the version number at 1.0.

I think my "clean up" might have made it worse, also it means that there could be older versions of these symbols and/or footprints somewhere in this repo that are different from what I described above.

As a solution, I think I need to:

• learn how to organize symbols and footprints across multiple KiCad projects.
• redo all the footprints and symbols to meet the common standard K=1, A=2
• do not re-use the old names for the new ones
• clean up all schematics and PCBs to use the new ones